Epilobium willow-herb
(For a dichotomous table for galls on Epilobium and Chamerion by Hans Roskam click here)Dichotomous table for leafminers
Dichotomous table for leafminers
See also the key for Chamerion.
1a larva in June-August => 2
1b larva in March-May => 3
1c galls, etc => Tables for all parasites per species
2a on lesser Epilobium-species; one or more short corridors radiating from the base of the midrib; later mine (may be on another leaf) an elongated blotch beginning at the midrib: Mompha locupletella
2b on Epilobium hirsutum; untidy corridor somewhere on the leaf; later mine a large blotch independent of the midrib: Mompha langiella
3a on lesser Epilobium-species; one or more short corridors radiating from the base of the midrib; later mine an elongated blotch that begins at the midrib: Mompha locupletella
3b on all Epilobium-species; blotch mines only => 4
4a lower-surface blotch, centered over the midrib; little or no frass: Mompha ochraceella
4b full-depth blotch without apparent association with the midrib; much coarse granular frass => 5
5a larva: anal shield light brown, feet dark brown: Mompha propinquella
5b anal shield and feet dark grey: Mompha lacteella
Not included in the key: Cnephasia incertana, Cnephasia stephensiana; Liriomyza strigata; Mompha epilobiella.